Perez averaged 7.28 K/9 last year, and 3.03 BB/9 over the course of 29.2 IP. While the strikeout numbers don’t immediately read “dominant reliever,” Perez generated 10.6 percent whiffs, and brought down a career average 5.03 BB/9 average.

The Mariners have had some trouble finding reliable lefty relievers in the Jack Zduriencik era, but last year they came up aces twice, picking Lucas Luetge in the Rule V draft, and signing Perez to a minor league contract.

This deal basically guarantees Perez a spot on the roster (though we thought the same about Hong Chi-Kuo last year, and he got cut in spring training). I’m not going to oversell this as a huge day in Mariners history. Perez was expected to be a LOOGY, though he dominated righties more than lefties, and was very good in a very small sample last year. He’s always had a ton of talent, but a hard time finding the strike zone. Perez pounded the strike zone last year, throwing pitches within the zone 55.9 percent of his pitches, and generating a disgusting 32 percent swing percentage on balls outside the zone.

Converting to a reliever, throwing only two pitches (seriously, 65 percent fastballs, 35 percent sliders) and recouping over 5.7 mph on your fastball can do that for a guy.